1. Field of the Invention
The present invention relates to an aspirator for a medical electronic endoscopic system, and particularly to an aspirator which is used for an endoscope system and able to perform an automatic intermittent aspirating operation.
2. Description of the Prior Art
Endoscopic systems are widely used for inspecting and treating subjects such as the duodenum, the rectum, the large intestine, the esophagus, the ear, the nose, the bladder, etc., of a body.
An aspirator for the endoscopic system keeps the view field of an optical observation system disposed at a front end of the endoscope clean during the operation.
Particularly, when the endoscope is used to inspect and treat an affected part on a digestive system of the body, obstacles such as mucus, vegetable residues and feculence around the subject may hinder the view field of the optical observation system so that they shall be drained by using the aspirator.
This aspiration work is indispensable and frequently required in a general inspection and treatment using the endoscopic system.
A conventional aspirator for the endoscopic system comprises a suction nozzle disposed at an end of an insertion portion of the endoscopic system, and a suction pump connected to the suction nozzle through a suction flask. The suction pump is continuously operated while an operator keeps a aspirator button disposed on a controlling portion turned ON, and removes obstacles such as feculence into the suction flask.
Such a conventional aspirator frequently causes a disadvantage that the suction nozzle sucks and sticks to the wall of a subject to be inspected.
The sticking to the wall not only hinders the view field of the endoscope by blocking its optical observation system with the wall, but also dangerously increases a negative pressure in the suction nozzle to perforate the wall with an edge of the endoscope if the wall is thin such as a large intestine.
Further, a conventional aspirator for the endoscopic system continues the aspirating work while its aspirator button is ON, so that an operator must alternately and intermittently push and rapidly release the button to avoid the risk of perforating the wall. Therefore, the operation is bothersome and increases fatigue of the fingers of the operator.
The present invention solves the above mentioned problems inherent to the conventional aspirator for the endoscopic system.